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Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
Selective halogenation at the pnictogen atom in Lewis-acid/base-stabilised phosphanylboranes and arsanylboranes
Karl-Christian Schwan1, Ariane Adolf, Christine Thoms
1Institute of Inorganic Chemistry, University of Regensburg, D-93040, Regensburg, Germany.
Abstract:
The halogenation of Lewis-acid/base-stabilised phosphanylboranes () and arsanylboranes () with CX4 (X=Cl, Br) leads selectively to the substitution of both protons at the pentel atom and the new compounds [(CO)5W(X2PBH2.NMe3)] (:X=Cl, :X=Br) and [(CO)5W(X2AsBH2.NMe3)] (:X=Cl, :X=Br), respectively, are obtained. The new products were comprehensively characterised by spectroscopic methods and by X-ray crystallography. While compounds and show an antiperiplanar arrangement of the Lewis acid (W(CO)5) and the Lewis base (NMe3) in the solid state, a synclinal arrangement in and , respectively, was observed. Computational calculations of the optimised antiperiplanar and synclinal geometries of the compounds and in the gas phase slightly favour the antiperiplanar arrangement of the Lewis acid and the Lewis base for both compounds.
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